


The Mari Welcome

by FaithWarrior



Series: The Bug in the Belfry [21]
Category: Batman - All Media Types, Miraculous Ladybug
Genre: Adopted Sibling Relationship, Badass Marinette Dupain-Cheng | Ladybug, Damian Wayne Needs a Hug, Damian Wayne-centric, Gen, Identity Reveal, Maribat Bio Dad Bruce Wayne Month, Marinette Dupain-Cheng | Ladybug is a Wayne, Sibling Bonding
Language: English
Status: Completed
Published: 2021-01-17
Updated: 2021-01-17
Packaged: 2021-03-15 14:49:13
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,199
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28815165
Author URL: https://archiveofourown.org/users/FaithWarrior/pseuds/FaithWarrior
Summary: For Maribat Bio!Dad Bruce Wayne Month 2020: Day 21 Rivalry.Continuation of Growing With The Times, Day 12: Baby Mari/Little Mari.Damian is the true blood son. Heir to the Demons head and the Bat. How will he deal with this new 'development'.
Relationships: Batfamily Members & Marinette Dupain-Cheng | Ladybug, Marinette Dupain-Cheng | Ladybug & Bruce Wayne, Marinette Dupain-Cheng | Ladybug & Damian Wayne, Marinette Dupain-Cheng | Ladybug & Jason Todd
Series: The Bug in the Belfry [21]
Series URL: https://archiveofourown.org/series/1905886
Comments: 9
Kudos: 332





	The Mari Welcome

**Author's Note:**

> Please read Growing With The Times first in order for this to make sense. Hope you guys like it.

_“No, not so little anymore. And for once I get to be the big sister.” Mari said with a smile. “Wanna help me give Dad a heart attack?”_

_“I guess that will be more satisfying than tormenting Gotham's criminals.” Jason concluded._

_“Yay. It’ll be the best. Someone is totally going to throw something at us.” Mari cheered._

_“Why?” He asked suspiciously._

_“Because Portals.” Marinette explained before transforming and merging the cat with the horse. “Call me Nightmare.”_

_“Adorable Pixie.” Jason said with raised eyebrows._

_“Yeah Yeah. Let's go. If I’m away from Paris for too long my partner is going to have a mental breakdown.” Mari said before calling on the horse's power._

_Both siblings stepped through the portal with matching smiles. It was time to give the Bat a scare, and a surprise or five._

***

Like every night Damian Al Ghul Wayne prowled the halls of the Manor and avoided the other residents. Many failed attempts to remove his father's false heirs had proved that the imposter was far more resilient, or lucky, than he had a right to be. Damian could also tell that there were things that were being hidden from him. He did not like being kept out of the loop, but his father had yet to respect his rightful place as blood heir. Even still Robin would be his in due time.

For now Damian wandered and settled for the meager entertainment Pennyworth provided during the day in the form of ‘education’. He would even concede that the servant was an accomplished cook, and the teas he served with Damians meals were of the highest quality. 

Of the household Grayson was most willing to interact with him outside of Pennyworth and the rare appearance of his father. And though it bit at Damian to admit the acrobat was an accomplished fighter in his own right. Their spars had become increasingly more entertaining as Damian absorbed his style. Sparing with Drake was rare considering that no one was oblivious to the distaste Damian showed to the usurper. The older boy was unnecessary but still treated with the same affection and care as Grayson. 

Damian had heard whispers among the younger vigilantes when they thought he wasn’t around about a mystery person only referred to as ‘Bean’ or ‘Sunshine’. On the occasions where father was a part of the conversation the man referred to this person as ‘Bluebell’. But no amount of digging Damian accomplished could uncover the identity of this mystery person that held so much importance to the residents of Wayne Manor.

During his stay in the Manor it had been made obvious that Damian had not earned the trust of his father or his household. He was restricted from patrols on the grounds of both his age and lack of non lethal training. Appearing in public was strongly discouraged without an escort due to his age, and the lack of awareness of his existence as of yet. And Damian was not trusted with the secrets that seemed to be shared by the rest of what was apparently his family. He knew that the loss of Todd was still a vivid scar in the manor, but he was unsure of how to address them with his own theories, or if he even could without betraying his mother. 

Within his wandering Damian made his way down to the cave. It was late, almost the time when father and the others would be getting back from patrol for the evening. If Damian couldn’t sleep he might as well pursue his father on letting him patrol with him.

The cave was empty but for Pennyworth at the computer. “Greetings Master Damian.” The man addressed without turning around. “Anything I can help you with?”

“Tch.” Was all Damian replied before taking a seat at one of the computers other monitors. “Uptick in chatter in Crime Ally but no increase in crimes.” Damian rattled off. One of his fathers exercises was to monitor the talk around the city so he could ‘understand the people’. It was busy work beneath Damians skills and he hated that it was all he was currently permitted to do.

“Very well Master Damian. Your father and brothers should be arriving back soon if you would like to wait with me.” Pennyworth was always saying things like that, like the imposters were his blood and not his competition.

Damian was pulled from his aggravated thoughts as two vehicles pulled into the cave. Nightwing was quick to tuck his bike into one of the garages as Batman and Robin exited the Batmobile. Everything was done with almost choreographed efficiency as all three vigilantes approached the computer at the same time. It was an almost intimidating scene of efficiency if not for the sudden appearance of a glowing blue circle to one side of the cave. Damian and Pennyworth quickly slipped on basic domino masks as two figures stepped through the portal before it closed. 

The larger figure was male and had a red helmet tucked under his arm. His black hair was broken up by a white streak that was familiar to Damian, and his leather jacket was one Damian had been contemplating over recently. The resurrected Jason Todd had a domino mask that prevented the other Waynes from recognizing him in his current state, but Damian had seen and trained with the man much more recently.

Beside Todd was a female figure dressed in dark gear similar to that of horse riders or trainers. It was toned with blacks and browns with subtle accents of electric blue and silver. The glasses on her face had solid black frames. She practically glowed with power. Then the girl actually glowed as her outfit transformed into one lacking the brown accents of the previous one. Most noticeable were the girls slitted blue cat eyes and fabric ears that matched her black domino mask. “Oh wow. You really did remember the coordinates.” The girl said cheerfully as the two approached casually despite the raised weapons of the vigilantes. Damian had his katana unsheathed but at his side. This girl exuded more magic energy than he had felt in quite a long time, and it was almost familiar.

“Who are you and why are you here?” Father addresses them.

Todd chuckles dryly and the girl lets out an almost musical giggle. Todd is the one to speak first. “Don’t recognize your own kids B?” He asks, triggering confusion from those gathered. “Didn’t think you’d forget about me so soon.” The girl elbows him after the last comment and Todd lets out a sound of complaint. “Fine. Kitty's got bite.” The man drawls. “The kid knows who I am, or at least he should.” All heads turn to Damian briefly. Damian panics a little, although he isn't sure of the details this was certainly not one of his mothers plans. Todd must see his confliction. “Talia ain't part of this little Demon. Sorry for putting you on the spot.” The last part is added after another assault from his female companion. The domino mask is gently peeled from Todd's face and tucked inside of his helmet. When Todd raises his head multiple gasps are heard.

“Jaybird?” Grayson asks, the first to find his voice. 

“What? How?” Father stumbles. Damian has never heard his father struggle for words in such a way. “You said Talia?”

“The Lazarus pits.” A feminine voice says in sync with Damians own. 

Todd starts laughing. The girl, presumably the one who answered along with Damian has a wry look in her slanted cat eyes. “Laugh it up JayJay.” She scolds him.

“I know you.” Drake decides to speak.

The girl nods with a twinkle in her eye. “Yes, you all do.” She answered before looking thoughtful. “Except Damian, although I’m glad to finally meet you.” The girl trains her eyes behind everyone on Pennyworth. “I was glad to hear that you liked the teas I sent.” 

Pennyworth chuckled but the girl didn't give the rest of them time to figure it out. “I decided that it was time to be gone with all of the identity shenanigans. After all, family is much more important than pesky secrets.” She shrugged and moved to lean against Todd as the man dwarfed her small figure. 

“Pixie.” Todd spoke up in amusement. “Why don't you put them out of their misery?”

The girl, Pixie, pouted. “It's Kitty Nuit, JayJay, and Timmy just about has it figured out.” She looks over all of them before turning back to the man. “Why won't you let me have my fun? You got your big reveal.” 

“You're about to give B and Big Bird a coronary even if replacement figures it out.” Todd bickers back. Damian is confused by what he is witnessing. Todd was hardly ever this open in his memories, usually when they were alone or Damian was injured.

“Birdies fine, he has a strong constitution. And I’m still mad at Daddy for not telling me I had a brother until after Timmy let it slip.” The girl waved off.

Suddenly Drake gasped and started coughing. This is exactly why Damian should be Robin, the boy couldn't even be surprised without it killing him. Not that Damian knew what he was surprised about, but that really wasn’t the point.

“Yay!” The girl said doing a backflip. “Timmy figured it out first, pay up Jay Jay.”

“That's cheating, no way B doesn't have it yet.” Todd whined before handing over his helmet.

“You’ll thank me when you aren’t running around in this affront to the eyes. I mean come on Jay Jay you couldn't find anything uglier?” The girl rambles off. “And just to make sure you can’t torture my sensibilities again, Cataclysm.” With a gentle touch the exterior of the red helmet disintegrates in her hands leaving behind only the layers of electronics and safety features. “How's that for control?” The girl cheers.

“Bluebell?” Father addresses.

The girl smiles. “See, Daddy got it second so I’ll design your new helmet free of charge.” 

“You would do that anyway Pixie Pop.” Todd groused.

“Sunshine.” Grayson announced with apparent clarity. 

Damian however was coming to a different conclusion. This girl might be the mystery person his family seemed to care about, but she was also something much more powerful and dangerous. “Black Cat.” He announced.

The cat clapped her hands. “At the moment, yes. In this form I am Kitty Nuit, wielder of the Black Cat, but usually I’m Ladybug.” Damian restrained himself from taking a step back. A wielder of creation and destruction wasn’t someone to be trifled with. Kitty Nuit wasn’t done talking though. “It’s nice to finally meet you little brother.” 

The girl was once again consumed by a bright light, this time green, before a girl in a hoodie and jeans was left in front of them. Her blue eyes were no longer cat-like, but instead they were familiar. The girl had his father's eyes.

“I’m Marinette Dupain- Cheng Wayne.” She introduced as she walked over to him. “It is a pleasure to meet you Damian Al Ghul Wayne.”

A sister, Damian had a sister. Bruce Wayne had a biological daughter. And from the looks of it not only was his half sister the holder of powerful magical objects, she was also older. Fighting for the right of heir Damian could do, but against the holder of one or both of the most powerful magical objects in existence. It looked like this was one rival he would not find easy to best.

To Damians surprise the girl, his sister, pulled Damian into a hug upon reaching him. Despite the tension in the people around them Marinette had him wrapped in her arms as if he belonged there. She whispered in his ear. “You have no idea how happy I am to finally meet you Damian. It's nice to hug someone as the bigger sibling for once, and I promise that you will never have to fear me. I know it may be hard to see this place as home right now, but family is more than blood.”

“Why?” He whispered back. Why is she so open to him, to all of them. They challenge her position as rightful heir, or rather their positions he supposes. 

Marinette pulled back and smiled. “Little brother, you have faced much pain in your life. Would you consent if I had a way to remove the taint of the pits from you? Some has already been removed from Jason, but I will not take your choice from you.” A hand soothed down Damians head in a gentle motion.

“But why?” Damian asked again. Removing the pit madness was a boon, and any favor of such rarity could not come free.

“I am not your rival for our father's affection Damian, I am your sister.” As Damian is lost to his own confusion he hears Marinette explain her current situation to the rest of the family. Apparently from what he gathered Marinette, as Ladybug, led a team of heroes in Paris fighting her own villain by the name of Hawkmoth. Somehow he wasn’t surprised to learn that his sister was also the Guardian of the uber powerful jewels that his grandfather had coveted at one point in time. 

Damian started laughing maniacally, drawing concerned and somewhat frightened looks from most in the room besides Marinette. 

“Hey little D, you okay?” Grayson asked tentatively.

Jason chuckled. “He just got hit by the Mari train full force.”

Damian turns to his sister. “My only biological sibling is an older sister who is not only the oddest person I have ever interacted with, but also the protector of a collection of artefacts my grandfather sought for half of his lifetime.”

Marinette pats his arm. “I’ll get Tikki and Plagg to take care of that nasty pit magic on you soon little brother. Ras Al Ghul should have heeded the basic rules of magic, balance must be sustained.”

Damian nodded. “Your villain seeks a wish.” She nods despite it not being a question. Damian picks up his katana from where he had dropped it when Marinette hugged him. “I will help you sister.” He declares.

He can feel the eyes on him but ignores the sensation. Marinette is the first person to truly stand in front of him as an equal, though her magic quite possibly makes her more formidable than even his training could offer.

“Now wait just a minute Damian.” His father tries to argue.

“Daddy.” Marinette's soft voice stops the man. Damian watches as father and daughter stare at each other in silent communication. He wonders if that could be possible for him to achieve. “I will be able to stay for a few days to make sure you don't turn into a group of walking disasters, but then I will have to get back to Paris. Damian is welcome to join me. His training in the league will help him maintain an even emotional state once the pit magic is removed. I will arrange for my partner to join us later in the week to help with the magic if that is acceptable to you dad. If not we will conduct it before entering Paris.” She possesses the same energy father does when laying out a plan, but this time Damian is included. “I know all of this is unexpected Dad, but let me help. Let Maman and Papa help.” She addresses the man softly.

“He isn’t a hero.” Father tries to argue. Damian feels a twinge in his chest.

“Yet.” Marinette argues. “Not all of us need to be Robin in order to spread our wings.” Her words were layered with a smile. 

“That was a bad pun even for me, Bug.” A raspy voice interrupted. All except Alfred and Jason reacted to the appearance of a floating creature who resembled a small black cat. “Plagg, gotta say I’m starting to understand how pigtails here has so much chaotic energy in her nature for a bug.”

“I don’t even wear pigtails anymore Plagg.” Marinette argued. “Everyone, Plagg is the kwami of the black cat miraculous. He's basically a tiny god that loves cheese.”

Damian bowed to the small god. The kwami cackled. “I like this one.” He said before settling into Damian's hair. “He would have made a pretty good cat, not like my Kid, but still good.” 

Marinette smiled lightly. “I was thinking Roarr at this point. Long could also fit, but he's better with Gami.”

The small being smirked as it examined Damian. He straightened himself under the perusal. “Good choice Guardian. Your brother will make a fine tiger.”

“Thank you Plagg.” Marinette answered graciously. “Now why don't we turn in for the night.” Damian is shuffled off by his sister up to the exit of the cave. He can hear the conversation pick up behind them as they leave. “Don’t worry. They should get most of the conflict out before tomorrow. Grandpa Alfie will make sure of it.”

Damian raises a brow at her. “You are odd.” He says.

Marinette lets out a bright laugh. “Very true little brother, but we are part of an odd family are we not?”

He thinks for a moment and nods. “I will concede to your point.” Damian looks at her. “Why are you nice to me?” 

Marinette frowns slightly. “You are my brother, and despite your upbringing you are still a child.” Her arm brushes slightly against his as they walk. “Dad isn’t the best with emotions, but you deserve to feel like you are a part of this family.”

“Thank you.” Damian says thoughtfully. “Those teas, they weren’t normal were they?” 

This time her laughter is layered with a hint of power, magic. “Not entirely Damian. The teas were an all natural blend that my former teacher used to make for meditation. I adjusted the recipes to include a bit of various potions that I felt might help you settle in. If I had known about the Lazarus magic I would have adapted appropriately, but _c'est la vie_.” She pulled at her sweater a little bit. “I had also spelled the hoodie I sent Timmy. A little luck goes a long way.”

Damian scowled. “I knew he couldn’t be that good at evading me.” He growled. Drake had been narrowly escaping his attempts for weeks.

“Oh he is that good. All my magic did was give him a larger probability of success at any given time. I’ve been working on adding charms to the clothing I make.” Her voice is flippant but Damian is impressed.

He stares at her. “You are now my favorite sibling.” He declares abruptly. 

Marinette grins brightly. “Yay.” She says cheerfully. “How do you feel about a panjas bracelet?” 

He tilts his head. “Curious.” Damian answered.

“Good.” She seems to decide. “Also I’m definitely going to make you some new clothes.” Marinette continues to ramble on happily.

Damian believes that he has found a new thing to rival his father's wards. Being Marinette's favorite sibling. 

Marinette would probably claim that he was her favorite younger brother, but that was just cheating.

**Author's Note:**

> I know updates on this series have been more spaced out recently. Bare with me and I hope you are still enjoying this series despite it not being anywhere close to September anymore. But hey its 2021 now, maybe I'll finish this before the next Maribat Bio!Dad Bruce Wayne Month, LOL.


End file.
